Retarding mechanism



June 11, 1929. E. P. RENAUX. 1,716,666

RETARDING MECHANISM Filed April 14, 1926 INVENTOR EUGENE P. RENAux ATTORNEY Patnte'd June ll, 1929.

UNITED, STATES- EUGENE PRO SPER RENAUX, OF PARIS, FRANCE'ASSIGNOR PANY, OF CHICAGO, ILLINOIS,

RETARDINQ Application filed April 14, 1926, Serial No.

This invention relates to brakes'and is illustrated as embodied in an internal expanding automobile brake.

An important object of the mventlon relates to Connecting the adjacent ends of a pair of brake shoes or other friction devices.

by power-multiplying means through which one of those devices operates the other, thus serving as a servo shoe. In one desirable arrangement the servo shoe, and a main brake shoe are arranged end to end and-engagedrum.

brake by means of a servo shoe or the like forced againstthe brake drum by an applying device having rolling engagement therewith,

thus permitting a very substantial lengthwise or circumferential movement of the brake shoe without complicating the operating connections.

The powenmultiplying means between the -main and servo shoes embodies in its construction substantialnovelty which, together with other novel combinations of parts and desirable particular constructions, will be apparent from. the following description of one illustrative embodiment of the invention shown in the accompanying drawings, in

which I The figure is a vertical section through the brake'just inside of the head of the drum and showing the shoes in side elevation.

The particular brake selected for illustration includes a rotatable drum 10 having the usual peripheral cylindrical braking flange,

within which is arranged the friction means. of the brake, which in this instance includes a main shoe 1 2 a'nchored on a pivot 14 carried by a backing plate 16 at the open side of the drum, together-with 'a floatingor unanchored servo shoe, 18. Such a servo shoe is sometimes referred to as a booster or relay shoe.

The shoe 12 is urged away from the drum by suitable means such as a return spring 20 connected at one end to the backing plate 16 and is moved about the anchor or pivot 14 force the main shoe against the 1,716,666 PATENT OF,FICE-.

T0 BENDIX BRAKE COM- A CORPORATION .OF ILLINOIS.

MECHANISM.

101,918, and in FranceIDecember 14, 1922.

by novel power-multiplying means or connections herein shown as including a cam 22 engaging a wear plate 24: at the end ofthe shoe and having an operating arm 26.- I prefer, as a convenient meansof operating arm 26, to provide'it with a pin oa ether part 28 projecting between apair of jaws 30 carried by a lever 32 pivotally'connected at 34 to one end of the servo "shoe '18, 1 consider it desirable that the lever 32-ishould be fulcrumed coaxially of the (lHIrnZ-IGon;;a ,suitable shaft or spindle 36 which/may be/a rear axle of the automobile or the knuckle.

The servo slice '18 is' forced against the drum 10, against the resistance of the return spring. 38 connected to the backing plate 16, v by means having rolling engagement with its dle ,of 'the front wheel innersurface and shown as a rol1er40,car-,

ried by a crank arm 42keyed ona shaft 441 journalled in the backing plate 16 and operated by any suitable driver-controlled con-- ncctions. 'It will be observed that the rolling engagement of the applying device with the shoe 18 permits that shoe to have a very substantial lengthwise or circumferential movement'which rocks thelever 82 to force the shoe 12 or equivalent retarding means against the drum. When the brake is released, the spring 38 swings the shoe 18 away from the drum, whereupon the spring 20 pulls the shoe 12 away from the drum and also acts to return the lever '3 2 to its i'dleor initial position. p

While e illustrative embodiment of the invention has been described 'in detail, it is not my intention to limit its scope to that particular embodiment or otherwise than by the terms of the appended claims. Most of the subject-matter herein claimed is to be regarded as divided from my prior'application No. 625,072, filed March 14, 1923.

I claim: 1 v

1. A brake for vehicle wheels, comprising a brake drum adapted to rotate with the wheel, a main brake shoe adapted to act upon said brake drum, a cam member for actuating said main brake shoc, an auxiliary friction memberhaving a surface concentric with the wheel and another surface adapted to engage said brake drum, a roller-carrying lever for pressing the friction member against the brake drum, operating'means controlling said roller-carrying lever and adapted to be actuated by the driver, and

means operatively connecting the friction member with the said cam member.

2.. A brake for vehicle wheels, comprising a brake drum adapted to rotate with the wheel, a main brake shoe adapted to act upon said brake drum, a cam member for actuating said main brake shoe, an auxiliary friction I brake drum, operating means controlling said roller-carrying lever and adapted to be actuated by the dr ver, a lever secured to the cam" member, and another lever having a recess embracing the free end of the first lever and pivoted to the friction member and upon the wheel hub.

3. A wheel brake comprising a rotary drum, a stationary support, a lever pivoted on the support, a brake shoe for engaging mounted on one end on the support, and a,

the drum pivotally mounted on the free-end or' the lever, actuating means for swinging the free end of the shoe into engagement with the drum, the lever permitting the shoe, to partake of the movement or the drum, a second shoe for engaging the drum pivotally member connecting the free end ot'the second shoe with the lever intermediate its ends for multiplying the tractive force applied to'the first shoe and applying it to the second shoe;

4. A wheel brake comprising a rotary drum, a stationary support, a lever pivoted on the support, a brake shoe for engaging the drum pivotally mounted on thetree end of the lever, actu ating means for swinging the free end of the shoe into engagement with the drum, the lever permitting the shoe to partake of the movement of the drum, a sec ond shoe for engaging the drum pivotally mounted at one end on the support, and a member connecting the free end of the second shoe with the lever for applying the rotary tractive force imparted to the first shoe as a substantially radial thrust on the second shoe.

5. A brake comprising, in combination, a

drum, a friction device engageable with the drum, a device 'for causing the'triction de- I vice to engage the drum and which has an operating arm, a servo friction device also engageable with the drum, and a lever engaged by the servo friction device and which is arranged to operate said arm.

6. A brake comprising, in combination, a plurality of friction'devices, a cam for operating one of the friction devices, an arm for rocking the cam, and a lever engaged by the other friction device and arranged to operate said arm.

7. A brake comprising, in combination, a drum, a pair of shoes'arranged end to end and engageable with the drum, and powermultiplying levers one of which is engaged 8. A brake comprising, in combination, a

drum, main and servo shoes engageable with the drum, a lever movable about a fixed fulcrum and pivotally connected to one end of the servo shoe, and a power-multiplying device acting on the main shoe and operated by movement of said lever with the servo shoe.

9. A brake comprising, in combination, a drum, main and servo shoes engageable with the drum, a lever pivotaliy connected to one,

end of the servo shoe and angularly moved by the servo shoe, and means engaging the adjacent end of the main shoe and operated by movement of the lever to force the main shoe against the drum.

10. A brake comprising, in combination, a drum, main and servo shoes engageable with the drum, and a'lever mounted for angular movement about the axis of the drum and pivotally connected to the servo shoe and arranged to force the main shoe against the drum.

i 11; A brake comprising, in combination, a

drum, main and servo shoes engageable with the drum, and a lever mounted for angular movement about the axis of the drum and pivotally connected to one end of the servoshoe.

12. A brake comprising, in combination, a drum, main and servo shoes engageable with the drum, means operated by movement of the servo shoe for forcing the mainshoe against the drum, and applying means having rolling engagement with the-servo shoe and forcing the servo shoe against the drum.

13. A brake comprising, incombination, a drum, main and servo shoes arranged end to end and engageable'with the drum, means between the adjacent ends of the main and servo shoes and operated by movement of the servo shoe to force the main shoe against the ion drum,and an applying device having rolling engagement with the servo shoe and .arranged to force the servo shoe against the drum,

drum, main and servo shoes arranged end to end and engageablewith the drum, powermultiplying connections between the adjacent ends of the shoes and operated by movement of the servo shoe to force the main shoe against the drum, and an applying device havinga rolling engagement with the servo shoe to force the servo shoe against the drum.

15. A brake comprising in combination, a drum, a pair of friction devices engageable with the drum, a lever rocked about its tulcr'um by themovement of one of the friction let. A brake comprising, in combination, a I

devices and formed with a pair of jaws, and

a deviceror applying the other friction de-.'

-vice having a part projecting between the jaws and operated by movement of the lever.

16. A brake comprising, in combination, a drum, retarding means frictionally engageable with the drum, a servo device, connections from the servo device to operate said able with the drum, a servo shoe, connections from the shoe to operate the retarding means, a member in rolllng engagement wlth the servo shoe, and means to move said member radially of the drum to bring the servo shoe into frictional engagement with the drum.

18. A brake comprising, in combination, a drum, retarding means frictionally engageable with the drum, a servo shoe, connections from the shoe tooperate the retarding means, a driver-operated crank member, and a memher pivotally supported by the crank member and having rolling engagement .With the servo shoe. I

In testimony whereof, I have hereunto signed my name.

EUGENE PROSPER RENAUXQ 

